The present invention relates to multi-ply braiding apparatus and, more particularly, to a new and improved apparatus for combing fibers in the area between a braiding machine and the braid point.
The process of braiding is distinguished from weaving in that all fibers are interchanged (moved) in a braiding cycle while in weaving only a single fiber (the fill) is moved through a fixed array of fibers (the warp). Multi-ply braiding is distinguished from conventional braiding in that more than two layers (plys) are formed by the process.
Any braiding process is characterized by the fact of all fiber carriers being in motion resulting in intertwined fibers. Multi-ply braiding machines use a matrix array of carriers capable of alternate row and column position shifts. Reversal of the direction of row and column motion during a complete shift cycle produces the intertwining of fibers. Production of complex shapes is possible by adjusting the length of travel (number of spaces shifted) of each row or column.
Multi-ply braiding concepts and machines are disclosed in the patents to Bluck U.S. Pat. No. 3,426,804, Florentine U.S. Pat. No. 4,312,261 and Brown U.S. Pat. No. 4,753,150. In the Bluck and Florentine patents, the teachings of which are incorporated herein by reference, each row and column consists of discrete eyelets or carrier blocks. In other machines presently in use, row motion is accomplished by shifting grooved track members containing fiber carriers. Column motion consists of shifting the discrete fiber carriers. In circular concepts, row motion is accomplished by shifting concentric rings or track members, as shown in FIG. 6 of the Florentine patent, or by shifting axially aligned rings of the same diameter in side by side relation, as shown in the Brown patent, the teachings of which are incorporated herein by reference. Column (radial or axial) motion again consists of shifting discrete carriers.
In braiding machines, it is necessary to comb the fibers in the area between the machine and the braid point for the purpose of preventing tangling of the fibers and producing a uniform braid. Up to the present time, such combing has been accomplished manually by hand or with rods. Manual combing is subject to certain disadvantages in that it is labor-intensive, slow and non-uniform, with the result that high-speed, automated braiding is not possible and uniform braids of a desired density are difficult to attain.
Accordingly, a need has arisen for an automated combing apparatus for a braiding machine or the like which can uniformly and rapidly comb fibers as they approach the braid point to produce uniform braids of a desired density.